Joshua Kuban

Dialysis Catheter Placement in Patients With Exhausted Access

Patients with end-stage renal disease undergo renal transplant, peritoneal dialysis, or intermittent hemodialysis for renal replacement therapy. For hemodialysis, native fistulas or grafts are preferred but hemodialysis catheters are often necessary. Per KDOQI, the right jugular vein is the preferred vessel of access for these catheters. However, in patients with long-standing end-stage renal disease vein thrombosis, stenosis and occlusion occurs. In these patients with end-stage vascular access, unconventional routes of placement of dialysis catheters are needed. These methods include placing them by means of sharp recanalization, via a translumbar route directly into the inferior vena cava, and via transhepatic and transrenal routes. These difficult, but potentially lifesaving methods of gaining vascular access are reviewed in this article.

Venous Diseases in Malignancy

Malignancy is known to induce a hypercoagulable state and literature evidence has long supported that a significant proportion of morbidity and mortality in patients with a known malignancy is attributable to thromboembolic events. A high incidence of venous and, to a lesser extent, arterial thrombosis is observed and in several instances a thromboembolic event such as deep venous thrombosis or pulmonary embolism may be the presenting event that leads to unmasking an underlying malignancy. This dates back to Trousseau’s astute description in 1860s of migratory thrombophlebitis harboring an occult malignancy [1].

Baseline Apparent Diffusion Coefficient as a Predictor of Response to Liver-Directed Therapies in Hepatocellular Carcinoma

Predicting outcomes in patients with hepatocellular carcinoma (HCC) who undergo locoregional therapies remains a substantial clinical challenge. The purpose of this study was to investigate pre-procedure diffusion weighted magnetic resonance imaging (DW-MRI) as an imaging biomarker for tumoral response to therapy for patients with HCC undergoing drug eluting embolic (DEE) chemoembolization and radioembolization. A retrospective review of HCC patients who underwent DEE chemoembolization or radioembolization was performed. Of the 58 patients who comprised the study population, 32 underwent DEE chemoembolization and 26 underwent radioembolization. There was no significant difference in median apparent diffusion coefficient (ADC) values across the two treatment groups (1.01 × 10−3 mm2/s, P = 0.25). The immediate objective response (OR) rate was 71% (40/56). Tumors with high ADC values were found to have a higher probability of OR within 90 days (odds ratio 4.4, P = 0.03). Moreover, index lesion specific progression free survival (PFS) was greater for high ADC tumors, independent of conventional predictors of treatment response (hazard ratio 0.44, P = 0.01). Low ADC was associated with poorer PFS (P = 0.02). Pre-procedure ADC < 1.01 × 10−3 mm2/s is an independent predictor of poorer immediate OR and index lesion specific PFS in patients with HCC undergoing DEE chemoembolization or radioembolization.

Palliative Embolization for Refractory Bleeding

Bleeding is a common and often challenging complication of malignancy. Etiologies of hemorrhage in this patient population vary, and bleeding may present as an acute, life-threatening emergency or a chronic, low-volume blood loss. For patients with advanced malignancies, interventions to manage bleeding must be balanced by the patients life expectancy and quality of life. As such, minimally invasive procedures such as transarterial embolization are useful therapeutic options in appropriately selected patients. There is a rich history of palliative transarterial embolization for refractory bleeding in cancer patients. This technique was first applied in the 1970s and has since become an established treatment tool for malignancy-related bleeding throughout the body. While the preponderance of published data comprised case reports and small retrospective studies, the use of embolization continues to expand as experience grows and techniques are refined. In this review, we summarize the literature and provide our perspective on embolization for refractory bleeding in cancer patients.

Portomesenteric Venous Stenting for Palliation of Ascites and Variceal Bleeding Caused by Prehepatic Portal Hypertension

BACKGROUND The purpose of this study was to evaluate percutaneous transhepatic portal vein stenting (PVS) for palliation of refractory ascites and/or variceal bleeding caused by extrahepatic portomesenteric venous stenosis in patients with pancreaticobiliary cancer. MATERIALS AND METHODS A single-institution, retrospective review of patients who underwent PVS between January 2007 and July 2015 was performed. A total of 38 patients were identified, of whom 28 met the inclusion criterion of PVS performed primarily for refractory ascites or variceal bleeding. In addition to technical success and overall survival, clinical success was measured by fraction of remaining life palliated. The palliative effect of PVS was also quantified by measuring changes in liver and ascites volumes after the procedure. RESULTS Technical success was 93% (26/28). Stent deployment involved more than one portomesenteric vessel in most patients (20/26). The cumulative probability of symptom recurrence at 6, 12, 18, and 24 months was 12%, 16%, 26%, and 40%, respectively. There was a significant difference (p < .001) in the probability of symptom recurrence, recurrence of abdominal ascites, and increase in liver volume between patients whose stents remained patent and those whose stents demonstrated partial or complete occlusion. The mean fraction of remaining life palliated was 87%. All but two patients were found to have improvement in clinical symptoms for the majority of their lives after the procedure. There were no major or minor complications. CONCLUSION As a low-risk procedure with a high clinical success rate, PVS can play a substantial role in improving quality of life in patients with portomesenteric stenoses. IMPLICATIONS FOR PRACTICE Portomesenteric venous stenosis is a challenging complication of pancreaticobiliary malignancy. Portomesenteric stenoses can lead to esophageal, gastric, and mesenteric variceal bleeding, as well as abdominal ascites. The purpose of this study was to evaluate the safety and efficacy of portal vein stenting (PVS) in patients with cancer who have symptomatic portal hypertension caused by portomesenteric venous compression. As a low-risk procedure with a high clinical success rate, PVS can play a substantial role in improving quality of life in patients with portomesenteric stenoses.

Minimally Invasive Treatments for Liver Cancer

While surgical resection and chemotherapy have remained mainstays in the treatment of both primary and metastatic liver cancers, various minimally invasive techniques have been developed to treat patients for whom traditional approaches either are not available or have failed. Percutaneous ablation techniques such as radiofrequency, microwave, cryoablation, and irreversible electroporation are considered as potentially curative treatments in patients with hepatocellular carcinoma with early-stage tumors. Transarterial chemoembolization (TACE) and radioembolization with yttrium-90 (Y-90) are palliative treatments that have improved survival in patients with unresectable disease. In this chapter, we discuss these minimally invasive techniques, the criteria for selecting appropriate candidates for treatment, and potential limitations to their use.